Selective herbicides based on a  substituted                                               phenylsulfonylaminocarbonyl-triazolinone

ABSTRACT

The present invention relates to selective-herbicidal compositions, characterized in that they contain an effective amount of the compound 2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one of the formula (I) 
     
       
         
         
             
             
         
       
     
     and/or of salts of the compound of the formula (I), and to the use of these compositions for the selective control of weeds in crops of cereals, in particular crops of wheat, and to methods for the selective control of weeds in crops of cereals by applying the compositions together with surfactants and/or customary extenders.

The invention relates to the use of the known compound2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I) shown below—alias4,5-dihydro-3-methoxy-4-methyl-5-oxo-N[[2-(trifluoromethoxy)-phenyl]-sulphonyl]-1H-1,2,4-triazol-l-carboxamide(CAS-Reg.-No.: 145026-88-6)—and its salts, in particular its sodium salt(CAS-Reg.-No. 181274-17-9), for the selective control of weeds in cropsof useful plants, in particular for controlling problematic weeds incereals.

Substituted phenylsulphonylaminocarbonyltriazolinones such as, forexample, the compounds2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-ethyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one,2-(2-trifluoromethoxy-phenyl-sulphonylaminocarbonyl)-4-methyl-5-ethoxy-2,4-dihydro-3H-1,2,4-triazol-3-one,2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methoxy-5-methyl-2,4-dihydro-3H-1,2,4-triazol-3-one,2(2-trifluoromethyl-phenylsulphonylamino-carbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneand2-(2-di-fluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-4-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneand their salts, processes for preparing these compounds and their useas herbicides are the subject of earlier patent applications (cf. EP-341489, EP-422 469, EP-507 171, U.S. Pat. No. 5,534,486). The individualabovementioned substituted phenylsulphonylaminocarbonyltriazolinoneshave a molecular structure which is very similar to that of the compound(I) to be used according to the invention but, in contrast to thiscompound, they show shortcomings in their activity or activity gaps inthe case of certain weeds.

Surprisingly, it has now been found that the compound2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one(I) and salts thereof, in particular the sodium salt of the compound ofthe formula (I), in comparison with the abovementioned structurallysimilar compounds, show considerably stronger activity against someweeds in cereal crops which are difficult to control, combined with verygood compatibility with cereal species, such as, in particular, wheat,and are therefore particularly suitable for the efficient and selectivecontrol of weeds in cereals, in particular in wheat. The activity gapsobserved with the abovementioned comparative compounds which are closelyrelated to (I) do not occur in the weed spectrum of the compound (I) andits salts.

The invention provides selective-herbicidal compositions, characterizedin that they contain an effective amount of the compound2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one of the formula (I)

and/or of salts of the compound of the formula (I), in particular oftheir sodium salt [referred to as “(I)—Na-salt” in the use examples].

The invention furthermore provides the use of the compound2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I)—above—and/or of salts of the compound of the formula(I), in particular of its sodium salt, for the selective control ofweeds in crops of cereals, in particular in crops of wheat.

The invention furthermore provides a method for the selective control ofweeds in crops of cereals, in particular in crops of wheat, which ischaracterized in that the compound2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I)—above—and/or salts of the compound of the formula(I), in particular its sodium salt, is/are applied with surfactantsand/or customary extenders in crops of cereals.

The compound of the formula (I) and its Na salt are already known (cf.U.S. Pat. No. 5,534,486—Examples 79 and 321).

The compound of the formula (I) and its salts have a broad herbicidalactivity. They can be used, for example, for controlling the followingweeds:

Dicotyledonous weeds of the orders: Sinapis, Lepidium, Galium,Stellaria, Matricaria, Anthemis, Galinsoga, Chenopodium, Urtica,Senecio, Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea,Polygonum, Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum,Rorippa, Rotala, Lindernia, Lamium, Veronica, Abutilon, Emex, Datura,Viola, Galeopsis, Papaver, Centaurea, Trifolium, Ranunculus, Taraxacum.

Monocotyledonous weeds of the orders: Echinochloa, Setaria, Panicum,Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Lolium, Bromus,Avena, Cyperus, Sorghum, Agropyron, Cynodon, Monochoria, Fimbristylis,Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea,Dactyloctenium, Agrostis, Alopecurus, Apera, Aegilops, Phalaris.

However, the use of the compound (I) and its salts is by no meanslimited to these orders but extends in the same manner to other plantsas well.

The compound of the formula (I) and its salts have strong herbicidalactivity and a broad spectrum of activity when used on the soil and onabove-ground parts of plants. They are suitable for the selectivecontrol of monocotyledonous and dicotyledonous weeds in monocotyledonouscrops, especially in cereals, in particular in wheat, both by thepre-emergence and by the post-emergence method.

Problematic weeds which can be controlled particularly well with thecompound of the formula (I) and its salts, in particular its sodiumsalt, and whose control is less likely to succeed with both conventionalherbicides and more recent compounds of a similar molecular structureare, in particular, Agropyron, Alopecurus, Amaranthus, Apera, Avena,Brassica, Bromus, Capsella, Digitaria, Echinochloa, Erysimum, Lolium,Matricaria, Phalaris, Poa, Polygonum, Setaria, Sinapis, Thlaspi andVeronica.

The compound of the formula (I) and its salts, in particular its sodiumsalt, can be converted into the customary formulations, such assolutions, emulsions, wettable powders, suspensions, powders, dusts,pastes, soluble powders, granules, suspension/emulsion concentrates,natural and synthetic materials impregnated with active compound, andvery fine capsules in polymeric substances.

These formulations are produced in a known manner, for example by mixingthe active compounds with extenders, that is liquid solvents and/orsolid carriers, optionally with the use of surface-active agents, thatis emulsifying agents and/or dispersing agents and/or foam-formingagents.

If the extender used is water, it is also possible to employ for exampleorganic solvents as auxiliary solvents. Suitable liquid solvents areessentially the following: aromatics, such as xylene, toluene oralkylnaphthalenes, chlorinated aromatics, such as chlorobenzenes,chlorinated aliphatics, such as chloroethylenes or methylene chloride,aliphatic hydrocarbons, such as cyclohexane or paraffins, for examplepetroleum fractions, mineral and vegetable oils, alcohols, such asbutanol or glycol and also their ethers and esters, ketones, such asacetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone,strongly polar solvents, such as dimethylformamide and dimethylsulphoxide, and also water.

Suitable solid carriers are: for example ammonium salts and groundnatural minerals, such as kaolins, clays, talc, chalk, quartz,attapulgite, montmorillonite or diatomaceous earth, and ground syntheticminerals, such as finely divided silica, alumina and silicates; suitablesolid carriers for granules are: for example crushed and fractionatednatural rocks such as calcite, marble, pumice, sepiolite and dolomite,and also synthetic granules of inorganic and organic meals, and granulesof organic material such as sawdust, coconut shells, maize cobs andtobacco stalks; suitable emulsifying and/or foam-forming agents are: forexample non-ionic and anionic emulsifiers, such as polyoxyethylene fattyacid esters, polyoxyethylene fatty alcohol ethers, for example alkylarylpolyglycol ethers, alkylsulphonates, alkyl sulphates, arylsulphonates aswell as protein hydrolysates; suitable dispersing agents are: forexample lignin-sulphite waste liquors and methylcellulose.

Tackifiers such as carboxymethylcellulose and natural and syntheticpolymers in the form of powders, granules or latexes, such as gumarabic, polyvinyl alcohol and polyvinyl acetate, as well as naturalphospholipids, such as cephalins and lecithins, and syntheticphospholipids, can be used in the formulations. Other possible additivesare mineral and vegetable oils.

It is possible to use colourants such as inorganic pigments, for exampleiron oxide, titanium oxide and Prussian Blue, and organic dyes, such asalizarin dyes, azo dyes and metal phthalocyanine dyes, and tracenutrients such as salts of iron, manganese, boron, copper, cobalt,molybdenum and zinc.

The formulations in general contain between 0.1 and 95 per cent byweight of active compound, preferably between 0.5 and 90%.

For the control of weeds, the compound of the formula (I) and its salts,as such or in the form of their formulations, can also be used asmixtures with known herbicides, finished formulations or tank mixesbeing possible.

Possible components for the mixtures are known herbicides, for exampleamidosulfuron, bentazon, bromoxynil, carfentrazone(-ethyl),cinidon(-ethyl), clodi-nafop(-propargyl), clopyralid, chlorsulfuron,chlortoluron, cyclosulfamuron, 2,4-D, diclofop(-methyl), difenzoquat,diflufenican, florasulam, flupyrsulfuron(-methyl, -sodium),pyraflufen(-ethyl), ethoxyfen, fenoxaprop(-ethyl),fluoroglycofen(-ethyl), flupropacil, fluroxypyr, iodosulfuron,isoproturon, mecoprop, metosulam, metribuzin, metsulfuron(-methyl),pendimethalin, prosulfocarb, pyridate, sulfosulfuron,thifensulfuron(-methyl), tralkoxydim, triasulfuron,tribenuron-(-methyl), trifluralin.

Mixtures with other known active compounds, such as fungicides,insecticides, acaricides, nematicides, bird repellents, plant nutrientsand agents which improve soil structure, are also possible.

The compound of the formula (I) and its salts can be used as such, inthe form of their formulations or in the use forms prepared therefrom byfurther dilution, such as ready-to-use solutions, suspensions,emulsions, powders, pastes and granules. They are used in the customarymanner, for example by watering, spraying, atomizing or scattering.

The compound of the formula (I) and its salts can be applied eitherbefore or after emergence of the plants. They can also be incorporatedinto the soil before sowing.

The amount of active compound used can vary within a substantial range.It depends essentially on the nature of the desired effect. In general,the amounts used are between 1 g and 1 kg of active compound per hectareof soil surface, preferably between 5 g and 0.5 kg per ha.

The use of the compound of the formula (I) and its salts can be seenfrom the following examples.

USE EXAMPLES

In the use examples, the compounds shown below are used as comparativesubstances:

2-(2-Trifluoromethoxy-phenylsulphonylaminnocarbonyl)-4-ethyl-5-methoxy-2,4-di-hydro-3H-1,2,4-triazol-3-one(known from EP-507 171, U.S. Pat. No. 5,534,486—Example 87)

2-(2-Trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-ethoxy-2,4-dihydro-3H-1,2,4-triazol-3-one—sodiumsalt—(known from U.S. Pat. No. 5,534,486—Example 260)

2-(2-Thfluoromethoxy-phenylsulphonylaminocarbonyl)-4-methoxy-5-methyl-2,4-dihydro-3H-1,2,4-triazol-3-one(known from EP-422 469—Example 96; see also U.S. Pat. No.5,057,144—Example 96)

2-(2-Trifluoromethyl-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one—sodiumsalt (known from EP-507 171, U.S. Pat. No. 5,534,486—Example 187)

2-(2-Difluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one—sodiumsalt (known from U.S. Pat. No. 5,534,486—Example 319)

2-(2-Chlorodifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one—sodiumsalt (in the claim of EP-507 171 and U.S. Pat. No. 5,534,486)

2-[2-(1,1,2,2-Tetrafluoroethoxy)-phenylsulphonylaminocarbonyl]-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one(in the claim of EP-507 171 and U.S. Pat. No. 5,534,486)

2-[2-(Pentafluoroethoxy)-phenylsulphonylaminocarbonyl]-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-one—sodiumsalt (in the claim of EP-507 171 and U.S. Pat. No. 5,534,486) EXAMPLE A

Pre-Emergence Test/Greenhouse

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent, thestated amount of emulsifier is added and the concentrate is diluted withwater to the desired concentration.

Seeds of the test plants are sown in normal soil. After about 24 hours,the soil is sprayed with the preparation of active compound such thatthe particular amount of active compound desired is applied per unitarea. The concentration of the spray liquor is chosen so that theparticular amount of active compound desired is applied in 500 ml ofwater per hectare.

After three weeks, the degree of damage to the plants is assessed in %damage in comparison to the development of the untreated control.

The figures denote:

-   -   0%=no effect (like untreated control)    -   100%=total destruction

In this test, for example, the sodium salt of the compound of theformula (I) exhibits, at an application rate of from 30 g/ha, verystrong activity (efficacy 80% to 100%) against weeds, such as, forexample, Alopecurus, Avena, Bromus, Digitaria, Echinochloa, Matricaria,Polygonum and Setaria, combined with very good compatibility with cropplants, such as, for example, wheat, whereas the comparative compounds(A), (C), (D), (E) and (F) exhibit considerably weaker herbicidalactivity and the comparative compound (B) is not compatible with wheat(cf. Table A1). The considerable superiority of (I)—Na-salt over thecomparative compound (G) is shown in Table A2 [“ai.”=“activeingredient”].

TABLE A1 Pre-emergence test/greenhouse Application rate Active (g ofcompounds ai./ha) Wheat Alopecurus Avena Bromus Digitaria EchinochloaSetaria Matricaria Polygonum (A) 30 0 20 0 40 0 50 60 0 0 (B) 30 50 7080 — — — — — 80 (C) 30 0 0 0  0 0  0  0 0 0 (D) 30 0 70 50 — 80 — — 3070 (E) 30 0 50 30  0 40 30 80 0 60 (F) 30 0 90 40 95 80 80 95 50 0 (I)-30 0 100 95 100  100 80 100  100 90 Na- salt

TABLE A2 Pre-emergence test/greenhouse Active Application rate compounds(g ai./ha) Alopecurus Avena Setaria (G) 250 50 0 50 (I)-Na-salt 250 10099 99

EXAMPLE B

Post-Emergence Test/Greenhouse

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent, thestated amount of emulsifier is added and the concentrate is diluted withwater to the desired concentration.

Test plants which have a height of 5-15 cm are sprayed with thepreparation of active compound such that the particular amounts ofactive compound desired are applied per unit area. The concentration ofthe spray liquor is chosen so that the particular amounts of activecompound desired are applied in 500 ml of water/ha.

After three weeks, the degree of damage to the plants is assessed in %damage in comparison to the development of the untreated control.

The figures denote:

-   -   0%=no effect (like untreated control)    -   100%=total destruction

In this test, for example, the sodium salt of the compound of theformula (I) exhibits, at an application rate of 60 g/ha, strong activity(efficacy 70% to 100%) against weeds, such as, for example, Agropyron,Alopecurus, Avena, Bromus, Lolium, Setaria and Veronica, combined withvery good compatibility with crop plants, such as, for example, wheat,whereas the comparative compounds (A), (B), (C), (D), (E) and (F) haveconsiderably weaker herbicidal activity (cf. Table B1). A considerablesuperiority of (I)—Na-salt (at 125 g/ha) over the comparative compounds(G) and (H) (in each case at 250 g/ha!) is shown in Table B2.

TABLE B1 Post-emergence test/greenhouse Application Active ratecompounds (g ai./ha) Wheat Agropyron Alopecurus Avena Bromus LoliumSetaria Veronica (A) 60 0  0  0  0 40 0 40 — (B) 60 0 — 40 — — 70 — 70(C) 60 0  0  0  0  0 0  0 0 (D) 60 0 — — — — — — 0 (E) 60 0 60 20 70  020 — 30 (F) 60 10 — 70 70 90 70 70 80 (I)-Na- 60 0 70 80 70 90 90 100 90 salt

TABLE B2 Post-emergence test/greenhouse Active Application ratecompounds (g ai./ha) Alopecurus Avena Setaria (G) 250 30 0 30 (H) 250 4080 20 (I)-Na-salt 125 90 90 95

EXAMPLE C

Post-Emergence Tests/Outdoors

In addition to the comparative compounds (B) and (D), the sodium salt ofthe compound of the formula (I) was tested under outdoor conditions inthe main cultivation areas of summer wheat in Canada againsteconomically important weeds. The small-plot experiments were carriedout on cultivated land under agricultural use. Areas with particularlyextensive weed growth were chosen preferably.

The active compounds were applied across the area by the spray method,with an average droplet size. To produce a useful preparation of activecompound, the active compounds were formulated as 70 WP (70% w/wwater-dispersible powder) and applied with customary amounts of water.Wetting of the plants was improved by addition of a surface-activesubstance (SAS) in the concentrations recommended by the respectivemanufacturer.

To assess the crop compatibility, from 1 to 8 weeks after the treatment,plant growth inhibitions or ailing of the leaf area were assessed in %damage in comparison to the development of the untreated control. Atdifferent intervals after the treatment, the herbicidal activity wasassessed as % reduction in comparison to the untreated control, based onthe weed development. The figures denote:

-   -   0%=no damage of the crops or no herbicidal effect,    -   100%=total destruction of the crops or the weeds.

The tests that were carried out show that the sodium salt of thecompound of the formula (I) has considerably stronger activity againstAvena fatua than the comparative compounds (B) and (D), combined withapproximately the same compatibility.

[“% w/w”=percentage by weight]

TABLE C Post-emergence tests/outdoors herbicidal effect herbicidaleffect herbicidal effect (%) (%) (%) (I)-Na-salt + Number (B) + SAS(D) + SAS SAS Test plants of tests (30 g of a.i./ha) (15 g of a.i./ha)(30 g of a.i./ha) Avena fatua 6 69 65 88 Setaria viridis 5 95 81 94Fallopia convolvulus 5 71 70 73 Sinapis arvensis 5 97 95 94 Thlaspiarvense 3 97 95 93 Crop damage 9 5 12 6 (wheat) SAS = “Canplus 411”(commercial product)

EXAMPLE D

Post-Emergence Tests/Outdoors

The sodium salt of the compound of the formula (I) was tested underoutdoor conditions in the main cultivation areas of summer wheat inCanada and the USA against economically important weeds. The small-plotexperiments were carried out on cultivated land under agricultural use,with cultivation and climate conditions which can be considered to berepresentative for the period of the trial. Areas with particularlyextensive weed growth were chosen by way of preference.

The active compound was applied across the area by the spray method,with an average droplet size. To produce a useful preparation of activecompound, the active compound was formulated as 70 WP or 70 WG (70% w/wwater-dispersible powder or granules) and applied with customary amountsof water. Wetting of the plants was improved by addition of asurface-active substance (SAS) in the concentration recommended by themanufacturer.

To assess the crop compatibility, from 1 to 8 weeks after the treatment,plant growth inhibitions or ailing of the leaf area were assessed in %damage in comparison to the development of the untreated control. Atdifferent intervals after the treatment, the herbicidal activity wasassessed as % reduction in comparison to the untreated control, based onthe weed development. The figures denote:

-   -   0%=no damage of the crops or no herbicidal effect,    -   100%=total destruction of the crops or the weeds.

The tests that were carried out show that the sodium salt of thecompound of the formula (I) is particularly suitable for controllingAvena fatua, Setaria viridis, Amaranthus retroflexus, Brassica spp.,Capsella bursa-pastoris, Sinapis arvensis and Thlaspi arvense incereals.

TABLE D Post-emergence tests/outdoors (I)-Na-salt + SAS (28-30 g ofa.i./ha) herbicidal effect Test plants Number of tests (%) Avena fatua263 90 Setaria viridis 102 94 Amaranthus retroflexus 60 90 Brassica spp.27 93 Capsella bursa-pastoris 12 90 Sinapis arvensis 48 98 Thlaspiarvense 45 97 Crop damage (wheat) 408 3 SAS = Agral, Agsurf, Canplus411, X-77 (commercial products)

1. Selective-herbicidal compositions, characterized in that they containan effective amount of the compound2-(2-trifluoromethoxy-phenyl-sulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I)

and/or of salts of the compound of the formula (I). 2.Selective-herbicidal compositions according to claim 1, characterized inthat they contain an effective amount of the sodium salt of the compoundof the formula (I).
 3. The use of the compound2-(2-trifluoromethoxy-phenylsulphonyl-aminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I) according to claim 1 and/or of salts of the compoundof the formula (I) for the selective control of weeds in crops ofcereals.
 4. The use of the sodium salt of the compound2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I) according to claim 1 for the selective control ofweeds in crops of cereals.
 5. The use of the compound2-(2-trifluoromethoxy-phenylsulphonyl-aminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I) according to claim 1 and/or of salts of the compoundof the formula (I) for the selective control of weeds in crops of wheat.6. Method for the selective control of weeds in crops of cereals,characterized in that the compound2-(2-trifluoromethoxy-phenylsulphonylaminocarbonyl)-4-methyl-5-methoxy-2,4-dihydro-3H-1,2,4-triazol-3-oneof the formula (I) according to claim 1 and/or salts of the compound ofthe formula (I) are applied together with surfactants and/or customaryextenders in crops of cereals.